From 48da06ec371421a48f801f6da1add6e437ccfa06 Mon Sep 17 00:00:00 2001
From: Alexander Gavrilov <angavrilov@gmail.com>
Date: Sat, 29 Sep 2012 15:18:04 +0400
Subject: [PATCH] Add an API function for reading the nominal skill level.

---
 LUA_API.rst                     |  5 +++++
 library/LuaApi.cpp              |  1 +
 library/include/modules/Units.h |  1 +
 library/modules/Units.cpp       | 21 ++++++++++++++++++---
 4 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/LUA_API.rst b/LUA_API.rst
index f532d2212..bf7ee45a7 100644
--- a/LUA_API.rst
+++ b/LUA_API.rst
@@ -918,6 +918,11 @@ Units module
   Returns the age of the unit in years as a floating-point value.
   If ``true_age`` is true, ignores false identities.
 
+* ``dfhack.units.getNominalSkill(unit, skill[, use_rust])``
+
+  Retrieves the nominal skill level for the given unit. If ``use_rust``
+  is *true*, subtracts the rust penalty.
+
 * ``dfhack.units.getEffectiveSkill(unit, skill)``
 
   Computes the effective rating for the given skill, taking into account exhaustion, pain etc.
diff --git a/library/LuaApi.cpp b/library/LuaApi.cpp
index b2d41dc19..dab99f48a 100644
--- a/library/LuaApi.cpp
+++ b/library/LuaApi.cpp
@@ -828,6 +828,7 @@ static const LuaWrapper::FunctionReg dfhack_units_module[] = {
     WRAPM(Units, isDwarf),
     WRAPM(Units, isCitizen),
     WRAPM(Units, getAge),
+    WRAPM(Units, getNominalSkill),
     WRAPM(Units, getEffectiveSkill),
     WRAPM(Units, computeMovementSpeed),
     WRAPM(Units, getProfessionName),
diff --git a/library/include/modules/Units.h b/library/include/modules/Units.h
index 65f0b58a0..2019eb652 100644
--- a/library/include/modules/Units.h
+++ b/library/include/modules/Units.h
@@ -233,6 +233,7 @@ DFHACK_EXPORT bool isDwarf(df::unit *unit);
 
 DFHACK_EXPORT double getAge(df::unit *unit, bool true_age = false);
 
+DFHACK_EXPORT int getNominalSkill(df::unit *unit, df::job_skill skill_id, bool use_rust = false);
 DFHACK_EXPORT int getEffectiveSkill(df::unit *unit, df::job_skill skill_id);
 DFHACK_EXPORT int computeMovementSpeed(df::unit *unit);
 
diff --git a/library/modules/Units.cpp b/library/modules/Units.cpp
index 01b7b50f4..2644f4ab2 100644
--- a/library/modules/Units.cpp
+++ b/library/modules/Units.cpp
@@ -876,7 +876,7 @@ inline void adjust_skill_rating(int &rating, bool is_adventure, int value, int d
     }
 }
 
-int Units::getEffectiveSkill(df::unit *unit, df::job_skill skill_id)
+int Units::getNominalSkill(df::unit *unit, df::job_skill skill_id, bool use_rust)
 {
     CHECK_NULL_POINTER(unit);
 
@@ -892,9 +892,24 @@ int Units::getEffectiveSkill(df::unit *unit, df::job_skill skill_id)
     df::enum_field<df::job_skill,int16_t> key(skill_id);
     auto skill = binsearch_in_vector(unit->status.current_soul->skills, &df::unit_skill::id, key);
 
-    int rating = 0;
     if (skill)
-        rating = std::max(0, int(skill->rating) - skill->rusty);
+    {
+        int rating = int(skill->rating);
+        if (use_rust)
+            rating -= skill->rusty;
+        return std::max(0, rating);
+    }
+
+    return 0;
+}
+
+int Units::getEffectiveSkill(df::unit *unit, df::job_skill skill_id)
+{
+    /*
+     * This is 100% reverse-engineered from DF code.
+     */
+
+    int rating = getNominalSkill(unit, skill_id, true);
 
     // Apply special states